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 ###Instrução: Qual é a frequência da estação wlfv-fm?
 ###Tabelas: CREATE TABLE meistriliiga_clubs_2013 (meistriliiga_clubs_2013_id AUTO_INCREMENT PRIMARY KEY, Club VARCHAR, Position in 2012 VARCHAR, First season in top division INT, Number of seasons in Meistriliiga INT, First season of current spell in top division INT, Top division titles INT) CREATE TABLE promotion_playoff (promotion_playoff_id AUTO_INCREMENT PRIMARY KEY, Position INT, Club VARCHAR, Played INT, Points INT, Wins INT, Draws INT, Losses INT, Goals for INT, Goals against INT, Goal Difference INT) CREATE TABLE stations (stations_id AUTO_INCREMENT PRIMARY KEY, DMA INT, Market VARCHAR, Station VARCHAR, Frequency VARCHAR, Branding VARCHAR, Format VARCHAR) CREATE TABLE list_of_games (list_of_games_id AUTO_INCREMENT PRIMARY KEY, Season INT, Date VARCHAR, Venue VARCHAR, City VARCHAR, Visitor VARCHAR, Score VARCHAR, Home VARCHAR, Attendance INT) CREATE TABLE grand_prix_motorcycle_racing_results (grand_prix_motorcycle_racing_results_id AUTO_INCREMENT PRIMARY KEY, Year INT, Class VARCHAR, Team VARCHAR, Points INT, Wins INT)  
SELECT Frequency FROM stations WHERE Station = WLFV-FM